The U.S. market for pet supplies and pet food is enormous, with retail sales of around $49 Billion in 2003 alone. As part of this market, there is an ongoing need for toys for pet dogs (and other pets), and a variety of designs have been produced. For example, some prior dog toy designs involve a twisted or knotted rope, often with frayed ends, that a dog can chew on and fetch. In U.S. Pat. No. 5,215,038 of O'Rourke, a dog chew toy uses a length of composite rope made of strands of sisal and cotton threads, with knots for a dog to chew on. Other dog toys use bone shapes featuring tennis balls, such as the plastic pet toy of U.S. Pat. No. 6,216,240.
Despite the variety of such known toys for pets, there is an ongoing need to produce pet toys that please both pet and owner.